The present invention relates to an electrode for detecting an electric biological signal, in particular an electrocardiographic signal.
Currently known instruments for detecting electrocardiographic signals present at least two external electrodes, which are applied to portions of the human body (e.g. one on the left and one on the right arm) for detecting electric biological body signals generated by the action of the heart.
The electrodes are substantially flat, and are normally applied to the body by means of straps or adhesive means on the electrode itself; and, to improve electrical contact between the electrode and the body, a thin layer of conducting gel is normally applied between the two. The layer of conducting gel, however, which is not applied evenly over the electrode and therefore varies in thickness, fails to provide for an optimum distance between the electrode and the body. In particular, on certain parts of the electrode, the thickness of the gel may be such as to present a contact resistance unsuited to the characteristics of the electrocardiographic signal detecting instrument.
Moreover, the above means of securing the electrodes fail to provide for rigidly connecting the electrically contacting parts, and permit relative movements resulting in noise in the electric signal, even to the extent of impairing the outcome of the electrocardiogram.